Many technologies exist for the packing of flexible packages, particularly bags or pouches, into containers. Some machines place or drop the packages flat in the container, others position the packages vertically within the container. Most of the machines available to place bags or pouches in a packing case with a vertical orientation tend to be large, expensive and capable of high speed operation.
The trend in many areas of manufacturing including the food industry is for more frequent product changeovers with shorter production runs. A concurrent trend is to reduce the number of packages in a shipping container. There is also constant economic pressure to reduce the cost, size and complexity of equipment, improve the flexibility of equipment and simplify processes.
A particular application of wide interest is the insertion of flexible bags or pouches, in one or more rows in a case or carton, where the bags or pouches are standing on end so that the top of every bag or pouch is visible from above. An ability to provide such a packing configuration, at least at moderate speed applications of up to about 140 cycles per minute is desired.
There have been numerous designs for machines to insert bags or pouches into cases such as those disclosed in US patent document Nos. U.S. Pat. No. 4,676,050 and U.S. Pat. No. 5,588,285 (by Odenthal). These overlap the bags so that as one bag is loaded vertically into a case, the top of the bag is prevented from tipping forward into the empty section of the case by the bottom of the next bag. However, the mechanism to do this includes insertion of the end of a conveyor mechanism into the case which, when withdrawn from the case after filling, leaves an unused void in the case that compromises the volume efficiency of the operation, otherwise known as ‘slack fill’.
A variant of this design is disclosed in German patent document No. DE 19917657, which fills the case in a different direction and uses different methods to prepare the group of bags to be loaded to the case, but which has a similar problem of slack fill.
A fast-operating machine which avoids the problem of slack fill due to a withdrawn conveyor is disclosed by Ferris in US patent document No. U.S. Pat. No. 5,855,105. The machine relies on angling of the cases and utilising gravity to encourage the bags to sit closely together, and thereby not fall into the unloaded portion area of the case. However, it is a considerably more complex, and hence expensive, machine. The machine further relies on gravity to compress the bags within the carton.
The issue of slack fill has been recognized and addressed in various patents, for example as disclosed by Benner, Dunhoft and Smith in US patent document No. U.S. Pat. No. 5,331,790 which specifically addresses the compression of a collated group of pouches to minimize the space required in the container into which the pouches are finally inserted. This mechanism is an example of the capable but rather complex, and hence expensive, designs that have been offered for higher speed operation.
The design disclosed by Saxrud and Hansen in US patent document No. U.S. Pat. No. 6,145,281 is one example of the method of creating a collated group of bags outside the carton and then inserting the group of bags into an erected carton or else erecting the carton around the group of bags. A variety of machines that collate the bags, condition them in appropriate ways and then place them inside a carton are offered by various of manufacturers. Although very effective, they are too complex and hence expensive to be cost effective for most low speed bag production processes.
A much simpler design for larger bags that also uses a tilted case to encourage bags to remain in the orientation in which they are placed is disclosed by Adamek in German patent document No. DE 19742017. It is relatively uncomplicated, but also relies on a bag ‘flying’from the end of a chute into a case and stopping in the required position in the required orientation in a consistent manner. Furthermore, subsequent bags must then find a stable position on top of the bags already loaded into the case, and sufficient clearance must be left within the case for the last bag to enter reliably. Bags filled with liquid may flex and thereby conform to the interior of the case, but bags containing solid materials are much less likely to do so solely under the influence of their own weight.
A slightly different approach is disclosed by Ryan in US patent document No. U.S. Pat. No. 4,608,808, in which bags are individually conveyed into a tilted case on a retractable conveyor. This has the same problem of slack fill, due to the space required in the case to accommodate the conveyor, as per Odenthal. It also requires the conveyor to be inserted and removed for each bag which will tend to slow down the process.
A different approach is disclosed by Didier in European patent document No. EP 1186537, where pouches are conveyed, without grouping, to special containers divided into a series of compartments. One pouch is dropped into each compartment with a subsequent process grasping the top of each of the individual pouches of a group prior to lifting the pouches out of the special container and placing them into a case. The plurality of special containers and the associated machinery costs can not usually be justified for most low speed applications.
Another approach, disclosed by Heliot in US patent document No. U.S. Pat. No. 3,425,184 is to guide individual bags into a cavity defined within a specialised case by the end, bottom and sides of said case and by the previously loaded bag restrained at its top by part of the mechanism and at the bottom by a feature of the special case. After the bag has fallen into the cavity, it is pushed along the inner surface of the case to be similarly restrained before the next bag falls into position. A plate mounted on an angled roller prevents the previously loaded bags from falling into the unused part of the case. This approach requires a special feature on the bottom of the case to restrain the lower end of the bag and also relies on a pusher to displace the bag beyond both the bottom feature and the top first restraining member of the mechanism. The pusher design requires that the bag be quite stiff and the first bag loaded will be displaced the entire length of the case, following bags must move correspondingly shorter distances within the case. Such systems are not suitable for many applications where the cost of providing a specialised case would be prohibitive, and the excessive sliding of the deposited items along the base of said container could not be reliably sustained due to the natural physical variations in said items.
To summarise the drawbacks of the prior art, each of the above described systems possesses one or more of the following features:                A conveyor extending into the case which reduces the space available to be filled with bags (Odenthal, Ryan and DE 19917657).        Bags or pouches are transferred into a tilted case individually (Ryan, Adamek) and gravity is relied upon to keep the bags or pouches in place. The bags must form a stable stack within the case yet the case must have sufficient width for the bags to enter easily.        A group of pouches is transferred into a case in a single operation, which requires considerable machine complexity (Saxrud and Hansen). Many other machines are available to load cases but they tend to be complex and expensive.        The product is placed into separate cavities in special containers to define their position prior to transfer to a case (Didier).        The product is guided into a cavity within a case where one side of the cavity is defined by the end of the case and must then be displaced within the case to provide room for the next bag or pouch (Heliot). The case requires special construction details for this process to work.        
It is an object of the present invention to provide an apparatus for automated packing of cases or cartons with vertically oriented bags or pouches, which overcomes at least some of the disadvantages of the prior art.